Gas Laws Problems

[Black _roses]

Theres a couple of questions that I dont know how to figure out.

1) What is the mass in grams of 14.82 L of NH₃ at10.0 degrees Celcius and 560 mm HG?

2) If you have 17L of oxygen gas at 680 mm Hg and 39 degrees Celcius, what is the mass in grams?

3) Synthetic diamonds can be manufactured at pressures of 6.00x10^4 atm. How many liters of gas, at standard pressure, would we need to create 6.66x10^-4L at 6.00x10^4 atm?

Can anyone help me?

[sharan]

1) What is the mass in grams of 14.82 L of NH₃ at10.0 degrees Celcius and 560 mm HG?
Answer: use PV =nRT
where P is 560mm Hg or (560/760)atm Use R = .082 Latm/ K mol Volume is 14.82 L T is 273 + 10 C=283 K, and find n
when you are done finding n which is number of moles
after finding n, say moles n = mass / molecular mass
where molecular mass of NH₃ = 14 + (1 x 3) = 15 gm/mol

2) If you have 17L of oxygen gas at 680 mm Hg and 39 degrees Celcius, what is the mass in grams?
Answer: same as above. find n first using PV=nRT (make sure to convvert celsius to kelvin and mmHg to atm and use R= 0.0821)
then n= mass/molecular mass molar mass of O₂ gas 2x16=32

3) Synthetic diamonds can be manufactured at pressures of 6.00x10^4 atm. How many liters of gas, at standard pressure, would we need to create 6.66x10^-4L at 6.00x10^4 atm?
Answer: use P₁V₁ = P₂ V₂ (boyle law temperature constant)
where P₁ is 6.00x10^4 atm V₁= 6.66x10^-4L
P₂ = 1 atm (standard pressure) V₂= ?
so just plug in and get answer ...


Hope that helps, ask if you face any type of confusion or problem in this..

-Sharan

[Black _roses]

Thank you.